Dog discovered biting bovine hard (8)
I believe the answer is:
foxhound
'dog' is the definition.
(foxhound is a kind of dog)
'discovered biting bovine hard' is the wordplay.
'discovered' becomes 'found' (finding is a kind of discovering**).
'biting' indicates putting letters inside (I've seen this in other clues).
'bovine' becomes 'ox' (ox is a kind of bovine).
'hard' becomes 'h'.
'ox'+'h'='oxh'
'found' placed around 'oxh' is 'FOXHOUND'.
(Other definitions for foxhound that I've seen before include "5 [MANS BEST FRIEND]" , "Hunting dog" , "hunter" .)